Antistatic polyethylene compositions containing water-insoluble aliphatic alcohols or ethyleneoxide condensation products



Patented can, lose msre'ric POLYE TIONS CONTAININ I ALIPHATIC ALconoLson THYLENE COMPOSI- G WATER-INSOLUBLE ETHYLENE- OXIDE CONDENSATIONPRODUCTS Geoflrey Philip Lee, St. Albans,

,Dunvegan MacLeod, Delwyn,

and Norman Garden City, England, assignors to Imperial ChemicalIndustries Limited, a corporation of Great Britain i No Drawing.Application July 11, 1947, Serial No. 760,502. In Great Britain July 16,1946 Claims. (01. 260-3L4 This invention relates to improvements inpolythene compositions and articles such as film, sheeting, filaments,coatings and the like prepared from polythene compositions. Polytheneconsists of polymers of ethylene corresponding substantially to theformula (cm): and may be solid, semi-solid or grease-like at ordinarytemperatures. The present inventionis concerned only with thoseforms ofpolythene which are solid at ordinary temperatures;

In the manufacture and use of film, sheeting, filaments, coatings andthe like comprising polythene there is a tendency for the material toaccumulate electrostatic charges. Such accumulated charges aretroublesome in that not only do they render the articles diflicult tomanipulate during manufacture, but they greatly increase the tendencyfor the articles to accumulate dust on their surfaces, which is aseriousdisadvantage when the articles are used for decorative purposes or asfurnishing materials, particularly when they have an irregularor'roughened surface.

It is an object of this invention to provide a process for reducing thetendency of polythene compositions and articles prepared therefrom toaccumulate electrostatic charges. A further object is to provide aneffective, inexpensive anti-static agent for polythene compositions andarticles prepared therefrom which does not react chemically withpolythene compositions or detract from the transparency or colour ofarticles prepared therefrom.

According to the present invention these objects are accomplished byaprocess which comprises treating polythene compositions or articlesprepared from polythene compositions with either a condensation productobtained by the interaction of ethylene oxide with either a waterinsoluble fatty alcohol or a. water-insoluble fatty acid, e. g. by theinteraction of from 1 to 20 mols of ethylene oxide with 1 mol of saidfatty alcohol preventing blooming.

or fatty acid; or with a saturated aliphatic alcohol containing morethan 12 but not more than 32 carbon atoms.

Saturated aliphatic alcohols which are particularly suitable for use inthe process of this in vention are myristic, cetyl and stearyl. It ispreferred, however, that one of the higher unsaturated alcohols,particularly oleyl alcohol, be added to the saturated alcohol, sincesome saturated alcohols, if used alone tend to bloom on the surface ofthe finished articles on storage. This addition of the oleyl alcoholdoes not appreciably affect the anti-static properties of the saturatedaliphatic alcohol. As far as the action of the oleyl alcohol is atpresent understood it appears to hold the saturated alcohol in a singlephase film on the surface of the polythene composition, preventing thesaturated alcohol appearing on the surface as solid particles, and soThe saturated aliphatic alcohols having radicals carbon atoms arepreferred for use in the process of this invention because they arereadily available.

The preparation of the which may be used in the process of thisinvention may be carried out by the method described in Britishspecification No. 380,431. The preferred condensation products arethoseobtained by the interaction of from 2 to 5 mols of ethylene oxide with 1mol of the water insoluble fatty alcohol or fatty acid, since productscontaining higher molecular proportions of ethylene oxide, e. g.proportions as high as 17 mols of ethylene oxide, while being initiallyeffective as anti-static agents, have a less permanent ei-Iect thantheproducts within the preferred ran'ge. Suitable -water insoluble fattyacids for use in forming taining about 44% cetyl alcohol with smalleramounts of myristic, stearyl andeicosyl alcohols. The acids derived fromcoconut oil contain about 45% by Weight lauric acid and smallerquantities of capric, myristic, palmitic and stcaric acid together witha small amount about 5% of the unsaturated acids oleic and linoleic.

The process of this invention is preferably operated by incorporatingfrom 0.1% to 5%, preferably from 0.5% to 1.5% by weight, of theantistatic agent With the polythene composition before the compositionis used in the fabrication of articles. The anti-static agent may beincorporated with the polythene composition by fiuxing in a suitablemixer, such as a. Banbury mixer. Articles prepared from polythenecompositions which do not contain these anti-static agents may, however,be treated by coating with the anti-static agent preferably by applyinga solution or dispersion of the agentin water or an organic liquid, andthereafter removing the solvent or dispersion medium by evaporation.

Our invention is illustrated but in no way limited by the followingexamples, in which all parts given are by weight.

containing 14, 16 or 18.

condensation products Example 1 400 parts of solid polythene, 6 parts ofa com-- asasi'eer vantage that they do not affect the mechanicalstrength'of the sheets or moulded articles, they are not toxic in thequantities used, they do not impart unpleasant odours to the-polytheneand theydo not discolour the articles in which they are incorporated.

Blue Lake 24480 (I. C. I.) were incorporated by fluxing in a Banburymixer... The mixture was thentransferred from the Banbury mixer to apair of malaxating rollers, which were steamheated sufliciently toprevent the mixture from solidifying and worked into a sheet which wasremoved from the rollers by means of a doctor knife and allowed to cool.

The sheet obtained was suitable for use in the fabrication of articlessuch as handbags, or for cutting into chips for use in the production ofmoulded or extruded articles. Articles formed from the material showed amarkedly reduced tendency to collect dust on their surfaces.

Example 2 As Example 1 except the mixture used consisted of 300 parts ofsolid polythene, 0.3 part diortho-cresylolpropane as a stabilizer, and 6parts of myristic alcohol. The sheet obtained showed little tendency tocollect dust on its surface.

Example 3 A sheet of material was made as in Example 1 from a mixtureconsisting of 300 parts solid polythene, 0.6 part of Red Seal zincoxide, 3 parts stearyl alcohol and 0.3 part Cadmium Scarlet 10106 (BlythColour Works). The sheet formed though showing little tendency tocollect dust on its surface, suffered from the defect of marked"blooming on the surface of the sheet.

Example 4 As Example 1, except that the mixture usedconsisted of 400parts of solid polythene, 4 parts of the product obtained by thecondensation of sperm oil alcohols with 2.5 molecular proportions ofethylene oxide, 0.4 part of zinc oxide (Red Seal) and 0.08 part ofCadmium Tangerine 10105 (BlythColour Works). The sheet obtained did notcollect dust and was free from blooming.

, Example 5 4 parts of the condensation product obtained by thecondensation of 1 molecule of N dodecyl alcohol with 3 molecules ofethylene oxide were mixed into 400 parts of solid polythene with theaddition of 0.04 part of Monastral Fast Green G. S. (I. C. I.) and asheet material produced from this mix by the method of Example 1. Theresultant product showed little tendency to collect dust on its surface.

Example 6 A sheet of material was prepared by the method described inExample 1 from a mixture consisting of 500 parts solid polythene and 5parts of the condensation product obtained by the condensation of theacids obtained from coconut oil and ethylene oxide. The mixtureof acidscontained 5% of capric acid, of lauric We claim: 7

1. An anti-static plastic composition essentially comprisingsolid'polythene and from 0.1% to 5%- by weight of said composition of amaterial selected from the group consisting of: (1) a condensationproduct resulting from the condensation 0132 to 5 mols ethylene oxideand one mol of a compound selected from the group consisting of waterinsoluble fatty alcohols, said alcohols hav ing from 6 to 20 carbonatoms and water insoluble fatty acids, said acids having from 10-28carbonatoms; *(2) a saturated aliphatic alcohol containing more than 12but not more than 32 carbon atoms; (3) a mixture of a; saturatedaliphatic alcohol containing more than 12 but not more than 32 carbonatoms and oleyl alcohol.

2. An anti-static plastic composition essentially comprising solidpolythene and from 0.5% to 1.5% by weight of said composition of amaterial selected from the group consisting of: (l) a condensationproduct resulting from the condensation of 2 to 5 mols ethylene oxideand one mol of a compound selected from the group consisting of waterinsoluble fatty alcohols, said to 1.5% by weight of said composition acondensation product resulting from the condensation of 2 to 5 mols ofethylene oxide and one mol of a compoundselected from the groupconsisting of water insoluble fatty alcohols, said alco-' \hOlS havingfrom 6 to 20 carbon atoms and water insoluble fatty acids, said acidshaving from 10-28 carbon atoms. t

4. An anti-static plastic composition essentially comprising solidpolythene and from 0.5% to 1.5% by weight of said composition of acondensation product resulting from the condensa-' tion reaction of 2 to5 mols ethylene oxide and 1 mol of water insoluble sperm oil alcohols.

5. An anti-static plastic composition essentially comprising solidpolythene and from 0.5% to 1.5% by weight of said composition acondensation product resulting from the condensation of 2 to 5 mols ofethylene oxide and one mol of a mixture of water insoluble fattyalcphols said mixture containing at least 44% cetyl alcohol and saidalcohols having from 6 to 20 carbon atoms.

GEOFFREY PHILIP LEE. NORMAN DUNVEGAN MACLEOD.

REFERENCES CITED r The following references are of record in the file ofthls'patent:

UNITED STATES PATENTS Number Name Date 2,342,400 Hopf Feb. 22, 19442,386,674 Flint Oct. 9, 1945 2,403,960 Stoops .i.--....- July 16, 1946

1. AN ANTI-STATIC PLASTIC COMPOSITION ESSENTIALLY COMPRISING SOLID POLYTHENE AND FROM 0.1% TO 5% BY WEIGHT OF SAID COMPOSITION OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF: (1) A CONDENSATION PRODUCT RESULTING FROM THE CONDENSATION OF 2 TO 5 MOLS ETHYLENE OXIDE AND ONE MOL OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF WATER INSOLUBLE FATTY ALCOHOLS, SAID ALCOHOLS HAVING FROM 6 TO 20 CARBON ATOMS AND WATER INSOLUBLE FATTY ACIDS, SAID ACIDS HAVING FROM 10-28 CARBON ATOMS; (2) A SATURATED ALIPHATIC ALCOHOL CONTAINING MORE THAN 12 BUT NOT MORE THAN 32 CARBON ATOMS; (3) A MIXTURE OF A SATURATED ALIPHATIC ALCOHOL CONTAINING MORE THAN 12 BUT NOT MORE THAN 32 CARBON ATOMS AND OLEYL ALCOHOL. 